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51.
A zero modes’ Fock space is constructed for the extended chiral WZNW model. It gives room to a realization of the fusion ring of representations of the restricted quantum universal enveloping algebra at an even root of unity, and of its infinite dimensional extension by the Lusztig operators We provide a streamlined derivation of the characteristic equation for the Casimir invariant from the defining relations of A central result is the characterization of the Grothendieck ring of both and in Theorem 3.1. The properties of the fusion ring in are related to the braiding properties of correlation functions of primary fields of the conformal current algebra model.   相似文献   
52.
A K Giri  L Maharana  R Mohanta 《Pramana》1997,48(5):1005-1013
We have analysed the two body non-leptonic charmed-meson decays of heavyB meson based on the factorization assumption. The transition matrix elements and the corresponding decay widths are calculated in the heavy quark and chiral symmetry limit and the Isgur-Wise function present in the expression is determined by the wave function model of Aliet al. The results obtained are quite interesting and agree reasonably well with the experimental data.  相似文献   
53.
在手征SU(3)夸克模型和扩展的手征SU(3)夸克模型的框架下,用变分的方法系统地研究了同位旋为0、1,自旋宇称为0~ 、1~ 和2~ 的ud■四夸克系统6个低组态的能量.模型的参数取自以前的工作,它能很好地描述核子-核子散射相移以及核子-超子散射截面.S道相互作用的参数由拟合K介子和K~*介子的质量定出,并且考虑了具有相同量子数的态之间的态混合效应.结果表明,同位旋为0且自旋宇称为1~ 的ud■能量低于相应的K~*K~*的阈能,且该组态中KK~*的成分相当小,因此该组态的宽度可能较小,可视为一个可能的四夸克态的候选者.  相似文献   
54.
In this report we investigate η-meson productions on the proton via electromagnetic and hadron probes in a chiral quark model approach. The observables, such as, differential cross section and beam asym-metry for the two productions are calculated and compared with the experiment. The five known resonances S_(11)(1535), S_(11)(1650), P_(13)(1720), D_(13)(1520), and F_(15)(1680) are found to be dominant in the reaction mech-anisms in both channels. Significant contribution from a new S_(11) resonances are deduced. For the so-called "missing resonances", no evidence is found within the investigated reactions. The partial wave amplitudes for π~-p→ηn are also presented.  相似文献   
55.
High spin states in A ~ 110 neutron-rich 106Mo, 110Ru and 112Ru nuclei have been reinvestigated by measuring the prompt γ-rays from the spontaneous fission of 252Cf. Two similar sets of bands are observed to high spins in each of three nuclei. Through analyzing of characters of the band structures, the chiral doublet bands are suggested in 106Mo, 110Ru and 112Ru.  相似文献   
56.
俞杭  徐锡方  牛谦  张力发 《物理学报》2018,67(7):76302-076302
在经典的物理学理论中,声子广泛地被认为是线极化的、不具有角动量的.最近的理论研究发现,在具有自旋声子相互作用的磁性体系(时间反演对称性破缺)中,声子可以携带非零的角动量,在零温时声子除了具有零点能以外还带有零点角动量;非零的声子角动量将会修正通过爱因斯坦-德哈斯效应测量的回磁比.在非磁性材料中,总的声子角动量为零,但是在空间反演对称性破缺的六角晶格体系中,其倒格子空间的高对称点上声子具有角动量,并具有确定的手性;三重旋转对称操作给予声子量子化的赝角动量,赝角动量的守恒将决定电子谷间散射的选择定则;此外还理论预测了谷声子霍尔效应.  相似文献   
57.
A quark meson coupling model based on SU(3)L×SU(3)R symmetry and scale invariance is proposed. The quarks and mesons get masses through symmetry broken. We apply this SU(3) chiral constituent quark model to investigating the nuclear matter at finite temperature and density. The effective baryon masses, compression modulus and hyperon potentials are all reasonable. The critical temperature of liquid-gas phase transition is also calculated in this model.  相似文献   
58.
寇谡鹏 《中国物理》2001,10(5):398-402
Using Parisi and Sourlas dimensional reduction, four-dimensional quantum chromodynamics is reduced to a two-dimensional principal chiral model by suitable superspace embedding. The frame Ta cannot be regarded as a fixed one and the frame connection field \varωμ(x) becomes a dynamical gauge field in two dimensions, giving rise to a confining potential. As a result of the original SU(3) Yang-Mills field obtains another SU(3) local symmetry and turns into SU(3)×SU(3) local symmetry-one group element as exp (iδ\varphiaTa) with fixed frame Ta, the other gauging the frame Ta.  相似文献   
59.
Using the model with one particle and one hole coupled with a triaxial rotor, the πg(-1)(9/2)(⊕)vh11/2 doublet bands in the A ~ 100 mass region are studied, and compared with the πh11/2(⊕)vh(-1)(11/2) doublet bands.It is found that the calculated results for the configuration of πg(-1)(9/2)(⊕)vh11/2 are very similar the results for a pure h11/2 proton particle and a neutron quasiparticle with λn =ε5. After including the pair correlation, the model describes the candidate chiral doublet bands in 106Rh successfully, which supports the interpretation of chirality geometry.  相似文献   
60.
We have theoretically investigated two-dimensional atom localization using the absorption spectra of birefringence beams of light in a single wavelength domain.The atom localization is controlled and modified through tunneling effect in a conductive chiral atomic medium with absorption spectra of birefringent beams.The significant localization peaks are investigated in the left and right circularly polarized beam.Single and double localized peaks are observed in different quadrants with minimum uncertainty and significant probability.The localized probability is modified by controlling birefringence and tunneling conditions.These results may be useful for the capability of optical microscopy and atom imaging.  相似文献   
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